The 1947 - Present Chevrolet & GMC Truck Message Board Network







Register or Log In To remove these advertisements.

Go Back   The 1947 - Present Chevrolet & GMC Truck Message Board Network > General Truck Forums > Suspension

Web 67-72chevytrucks.com


Reply
 
Thread Tools Display Modes
Old 11-06-2024, 08:13 PM   #1
Baketown Scotty
Junior Member
 
Baketown Scotty's Avatar
 
Join Date: Oct 2005
Location: Bakersfield, CA
Posts: 310
Front Shackle Hole Diameter

1966 GMC Suburban 4x4

Installing new shackle assembly on the rear front leaf springs. The holes in the shackles are not large enough to go past the threads onto the smooth section of the bolt. One side is slightly larger than the other allowing the one side to just start onto the smooth section. I can force them on a bit more but I'm sure I will destroy the threads. With the shackles on this far or even farther the shackles will not rotate from front to back, like they are practically pressed on. Should I open up these holes so they will rotate or are they supposed to be that tight?
Attached Images
   
__________________
1964 Chevy Suburban 4x4
1966 GMC Suburban 4x4
Baketown Scotty is offline   Reply With Quote
Old 11-08-2024, 02:41 PM   #2
Baketown Scotty
Junior Member
 
Baketown Scotty's Avatar
 
Join Date: Oct 2005
Location: Bakersfield, CA
Posts: 310
Re: Front Shackle Hole Diameter

Maybe I am thinking about this all wrong. Should the shackles not swing freely and only swing front to back by the weight of the vehicle?
__________________
1964 Chevy Suburban 4x4
1966 GMC Suburban 4x4
Baketown Scotty is offline   Reply With Quote
Old 11-08-2024, 07:17 PM   #3
leegreen
Registered User
 
Join Date: Mar 2022
Location: Surrey BC
Posts: 907
Re: Front Shackle Hole Diameter

Do you have the old shackles for comparison?

The shackles should swing back and forth. The diagram shows a greaseable bushing in each.

I'd expect the shackle to tighten down onto the shaft so the shaft turns in the bushing. You describe the shackles as almost fitting over the shaft, this does not sound right, I'd expect a more significant shoulder to tighten to. Are the holes stepped?

Maybe take the grease seals off, put it back together and see how it looks moves. If it is just the grease seal binding that is making it stiff it will soon free up. But the fit of shackles onto pin needs to be secure
leegreen is offline   Reply With Quote
Old 11-09-2024, 04:47 PM   #4
Baketown Scotty
Junior Member
 
Baketown Scotty's Avatar
 
Join Date: Oct 2005
Location: Bakersfield, CA
Posts: 310
Re: Front Shackle Hole Diameter

Lee green, you are correct. LMC sent lock nuts and instead of lock washers and nuts. Without the lock washers there is room to tighten the shackle down on to the smooth area of the pin. The shackles are in there tight but with the greased bushing rotating that will work just fine. Thank you for the help.
__________________
1964 Chevy Suburban 4x4
1966 GMC Suburban 4x4
Baketown Scotty is offline   Reply With Quote
Old 11-19-2024, 11:47 AM   #5
kwmech
Senior Member
 
Join Date: Mar 2003
Location: Colfax-California
Posts: 8,624
Re: Front Shackle Hole Diameter

Personally I wouldn't go off what LMC has to say. I've been getting nothing but crap from them lately and am moving on to other suppliers. Get rid of the hardware they gave you and go with a Gr 8 bolt. Later model front shackle bolts were 7/16 for quite a while and later upgraded to 1/2''. I dont know what you have there, but I've never seen lock washers on shackles, they've always been a self locking crimp nut on the factory stuff. Aftermarket usually uses the same style setup. Looking like that does, it appears the shackle plate has to sit on the shoulder of the bolt to leave room for the nut to get full thread contact. That is of course you are trying to go with all period correct looking OE stuff.
kwmech is offline   Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -4. The time now is 07:23 AM.


Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Copyright 1997-2022 67-72chevytrucks.com